Foaming body-cleansing agents

ABSTRACT

A foaming aqueous body-cleansing composition of (a) an anionic surfactant, (b) an alkyl (oligo)glycoside, (c) a zwitterionic surfactant, (d) an ampholytic surfactant is presented. The body cleansing composition produces a stable, fine-bubble, creamy-feeling foam.

This application filed under 35 U.S.C. 371 and based on PCT/EP97/06556,filed Dec. 2, 1996.

BACKGROUND OF INVENTION

1. Field of the Invention

This invention relates to foaming body-cleansing compositions in theform of a liquid surfactant composition based on a combination ofhigh-foaming anionic surfactants and foam-boosting alkyl(poly)glycosides which contain a combination of a zwitterionicsurfactant and an ampholytic surfactant for further improving theproperties of the foam, more particularly its fine-bubble character andits stability (creaminess).

Liquid body-cleansing compositions which are marketed, for example, asliquid soaps, shampoos, shower bath preparations and foam bath additivesare not only expected to have a good cleansing effect, they are alsoexpected to show high skin and mucous membrane compatibility and not tooverly degrease or dry the skin, even in the event of frequent use. Inaddition to this, however, consumers also evaluate performanceproperties according to the quality and quantity of the foam formed inuse. In particular, consumers look for rapid initial foaming withformation of a fine-bubble and stable foam, these properties of the foamalso being generally described as creaminess.

The body-cleansing formulations themselves are also expected to bedistinguished by a certain viscosity so that, for example, they can beapplied to the hand and do not trickle through the fingers before theycan be spread over the body or the head.

There are many known surfactants which are kind to the skin andcompatible with the mucous membrane. However, there are only a fewsurfactants which meet the additional need for a certain viscosity ofthe aqueous solution and for a fine-bubble character of the foam. Forthis reason, combinations of various surfactants have always been usedhitherto in order to satisfy these various requirements. Thus, acombination of alkyl ether sulfate surfactants and alkyl(poly)glucosides has proved to be particularly high-foaming anddermatologically compatible. In addition, zwitterionic surfactants orbetaine surfactants and ampholytic surfactants are known for theirability, in combination with anionic surfactants, to improve thedermatological compatibility of those surfactants and to Impart arelatively high viscosity to aqueous preparations or to improve theirthickenability by electrolyte salts.

2. Discussion of Related Art

DE-A-42 34 487, for example,describes an aqueous detergent compositioncontaining alkyl sulfate surfactants, alkyl ether sulfate surfactants,alkyl (oligo)glucosides and amphoteric or zwitterionic surfactants.

However, it has now been found that the properties of the foam, moreespecially its fine-bubble character and stability, can be furtherimproved by using a combination of a zwitterionic surfactant and anampholytic surfactant instead of a betaine surfactant or ampholyticsurfactant.

DESCRIPTION OF THE INVENTION

Accordingly, the present invention relates to aqueous body-cleansingcompositions containing high-foaming, dermatologically compatibleanionic surfactants (A) and alkyl (oligo)glycosides (B), characterizedin that they contain a combination of a zwitterionic surfactant (C)corresponding to formula I:

and an ampholytic surfactant (D) corresponding to formula II:

in which R¹ is an alkyl or alkenyl group containing 12 to 18 carbonatoms or a group R⁵—CONH—(CH₂)_(n), where R⁵ is an alkyl or alkenylgroup containing 12 to 18 carbon atoms and n is a number of 2 to 4, andR², R³ and R⁴ are alkyl groups containing 1 to 4 carbon atoms orhydroxyalkyl groups containing 2 or 3 carbon atoms,

in a ratio by weight of (A) to (B) to (C+D) of 10:(0.5-5):(1-5)

in order further to improve their foam properties and their viscosity.

High-foaming, dermatologically compatible anionic surfactants (A) areknown to the expert in large numbers from relevant handbooks and arecommercially available. More particularly, they are alkyl sulfates inthe form of their ammonium or alkanolammonium salts, alkyl ethersulfates, alkyl ether carboxylates, acyl isethionates, acylsarcosinates, acyl taurines with linear alkyl or acyl groups containing12 to 18 carbon atoms and in the form of their alkali metal or ammoniumsalts. The anionic surfactants (A) may be present in the compositionsaccording to the invention in a quantity of 3 to 30% by weight.Particularly preferred anionic surfactants are alkyl ether sulfates.Accordingly, at least one alkyl ether sulfate surfactant correspondingto the formula III:

R⁶O(C₂H₄O)_(m)—SO₃ ⁽⁻⁾M⁽⁺⁾  (III)

in which R⁶ is an alkyl or alkenyl group containing 12 to 18 carbonatoms, m=1-4 and M⁽⁺⁾ is an alkali metal, magnesium, ammonium oralkanol-ammonium ion, is preferably present as the anionic surfactant ina quantity of at least 5% by weight, based on the composition as awhole.

Alkyl (oligo)glycosides (B) are well-known surface-active substanceswhich can be produced from sugars and aliphatic primary alcoholscontaining 8 to 22 carbon atoms by acetalization. Sugar components(glycoses) include—preferably—glucose and also fructose, mannose,galactose, talose, gulose, allose, idose, arabinose, xylose, lyxose,ribose and mixtures thereof. The acetalization products of glucose withfatty alcohols obtainable, for example, from natural oils and fats byknown methods are preferably used by virtue of their ready accessibilityand their favorable applicational properties.

So far as the glycoside unit is concerned, both monoglycosides andoligoglycosides where a sugar unit is attached to the fatty alcohol by aglycosidic bond are suitable. Mixtures of mono- and oligoglucosides areusually present in the commercially available products.

Preferred alkyl (oligo)glycosides (B) are those with the formulaR⁷(G)_(x), where R⁷ is a linear alkyl group containing 8 to 16 carbonatoms and (G)_(x) is an (oligo)glucoside unit with an average degree ofoligomerization x of 1 to 2.

Such products are commercially available, for example, under the trademark Plantaren® or Plantacare®.

Zwitterionic surfactants (C) corresponding to formula I are alsowell-known and are commercially available in large numbers. The mostwell-known and most widely used group of these surfactants are thebetaine surfactants in which R² and R³ are methyl groups. Among thebetaine surfactants, there are the alkyl betaines where R¹ is an alkylor alkenyl group and the amidobetaines where R¹ is a groupR⁵CONH—(CH₂)_(n)—. A cocoamidopropyl betaine of formula I, where R¹ is agroup R⁵CONH—(CH₂)₃—, in which R⁵CO is derived from a C₁₂₋₁₈ cocofattyacid or palm kernel oil fatty acid, and R² and R³ are methyl groups, ispreferably used for the purposes of the invention. Such products arecommercially available, for example, under the trade mark Dehyton®K.

Ampholytic surfactants (D) corresponding to formula II are also knownand commercially available surfactants. They have the ability to reactlike cationic surfactants in acidic solution by protonation at thetertiary nitrogen atom and like anionic surfactants in the alkalinerange by salt formation at the carboxyl group. A preferred ampholyticsurfactant (D) is a cocoamphoglycinate corresponding to formula II whereR¹ is a group R⁵CONH—(CH₂)₂—, in which R⁵CO is derived from a C₁₂₋₁₈cocofatty acid or palm kernel oil fatty acid, and R⁴ is a hydroxyethylgroup. One such surfactant is commercially available, for example, underthe trade mark Dehyton®G.

Particularly favorable foam properties, more especially fine bubbles andcreaminess, are obtained when the zwitterionic surfactant (C) and theampholytic surfactant (D) are present in a ratio by weight of (C) to (D)of 1:(0.1-0.5).

Besides the compulsory components (A), (B), (C) and (D), the foamingaqueous preparations according to the invention may also contain othersurfactants and additives. In quantitative terms, these otheringredients together should not make up any more than component (A).

Suitable other additives are, for example, nonionic surfactants,water-soluble polymers, for example cationic polymeric conditioners,pearlescers, dyes, fragrances and emulsifiers suitable therefor,water-soluble polyols such as, for example, glycerol, sorbitol,propylene glycol or polyethylene glycol, electrolyte salts, pHregulators and cosmetic or dermatological agents.

If the total content of components (A) and (B) is less than 10% byweight, the viscosity of body-cleansing compositions according to theinvention may still be unsatisfactory. One particular advantage of thecompositions according to the Invention is that, in cases such as these,viscosity can readily be increased by the addition of water-solubleinorganic electrolyte salts.

Suitable inorganic electrolyte salts are any water-soluble alkali metal,ammonium and alkaline earth metal salts, for example the fluorides,chlorides, bromides, sulfates, phosphates, nitrates and hydrogencarbonates, providing they are soluble in water at 20° C. in a quantityof at least 1% by weight. Sodium chloride and magnesium chloride arepreferably used.

The body-cleansing compositions according to the invention may beformulated as highly concentrated pastes with a water content of lessthan 30% by weight H₂O or as dilute aqueous solutions containing lessthan 5% by weight of the anionic surfactant (A). However, the content ofanionic surfactants (A) is preferably in the range from 5 to 20% byweight In this range, body-cleansing compositions according to theInvention suitable for use as shampoos or shower gels can be formulatedwith viscosities in the range from about 1 to 200 Pa·s(20° C.).

The following Examples are intended to illustrate the invention:

EXAMPLES

I. Surfactants Used

Texapon ®N70: C_(12/14) cocofatty alcohol-2 EO-adduct sulfate, Na salt(70% paste) Dehyton ®K: Cocoamidopropyl Betaine (30% solution)    (+)    (−) R-CONH—(CH₂)₃—N(CH₃)₂—CH₂ COO R¹CO = acyl group of C₈₋₁₈cocofatty acid Dehyton ®G: Cocoamphocarboxyglycinate (30% solution)R²-CONH—(CH₂)₃—NH(CH₂CH₂OH) CH₂—COOH R²CO = acyl group of C₈₋₁₈cocofatty acid Plantacare ®818: C₈₋₁₄ alkyl polyglucoside (50% solution)R³-(G)_(x), R³ = C₈₋₁₄-n-alkyl group x = 1.4 G = glucoside unitCetiol ®HE: PEG7 Glyceryl Cocoate Euperian ®PK 810: Pearlescingconcentrate containing glycol di- stearate and Texapon N70.

II. Evaluation of Foam Volume and Quality

Foaming behavior and foam properties were tested in a standardized armwashing test. 2 g of the composition were applied to the wet hand andspread over the hands and forearms. After 1 minute, the composition waswashed off with water (15° C.). Foaming behavior, foam volume andcreaminess were evaluated by ten examiners. Their scores were averaged(1=poor, 2=adequate, 3=good, 4=very good).

Formulations

% by weight 1 2V 3V 4V 5V 6V Texapon N 70 15 15 15 17 18 16 Plantaren818 2 2 2 4 — — Dehyton K 6 8 — — — 6 Dehyton G 2 — 8 — 2 2 Eurperlan PK810 2 2 2 2 2 2 Cetiol HE 0.5 0.5 0.5 0.5 0.5 0.5 Merquat 550 0.5 0.50.5 0.5 0.5 0.5 Sorbitol 1.5 1.5 1.5 1.5 1.5 1.5 Glycerol 1.0 1.0 1.01.0 1.0 1.0 Sodium benzoate 0.4 0.4 0.4 0.4 0.4 0.4 Lactic acid 0.1 0.10.1 0.1 0.1 0.1 Citric acid 0.4 0.4 0.4 0.4 0.4 0.4 Perfume oil 1.3 1.31.3 1.3 1.3 1.3 Water 67.3 67.3 67.3 71.3 72.3 68.3 NaCl 0.2 0.2 0.2 0.20.2 0.2 Foaming behavior 2.9 2.1 1.8 2.0 2.0 1.9 Foam volume 3.0 2.3 2.02.0 2.0 1.9 Creaminess, fine-bubble 3.5 2.2 2.5 2.1 2.1 2.1 characterViscosity Pa.s (20° C.) 9.5 4.0 15.4 <1.0 <1.0 6.1 Haake Rotovisko,Spindle 2

What is claimed is:
 1. A foaming liquid aqueous body-cleansingcomposition comprising: (a) from 3 weight percent to 30 weight percentbased on the total weight of the composition, of an anionic surfactant,wherein the anionic surfactant comprises an alkyl sulfate in theammonium or alkanolammonium salt form, or an alkyl ether sulfate, alkylether carboxylate acyl sethionate, acyl sarcosinate, or acyl taurinewith linear alkyl or acyl groups containing 12 to 18 carbon atoms in thealkali metal or ammonium salt form, or mixtures thereof; (b) an alkylglycoside, an alkyl oligoglycoside or mixtures thereof; (c) azwitterionic surfactant corresponding to formula I:

 wherein R¹ is an alkyl or alkenyl group containing 12 to 18 carbonatoms or a R⁵—CONH—(CH₂)_(n) group, wherein R⁵ is an alkyl or alkenylgroup containing 12 to 18 carbon atoms and n is a number of from 2 to 4,and R² and R³ are alkyl groups containing 1 to 4 carbon atoms orhydroxyalkyl groups containing 2 or 3 carbon atoms; and (d) anampholytic surfactant corresponding to formula II:

 wherein R¹ is an alkyl or alkenyl group containing 12 to 18 carbonatoms or a R⁵—CONH—(CH₂)_(n) group, wherein R₅ is an alkyl or alkenylgroup containing 12 to 18 carbon atoms and n is a number of from 2 to 4,and R⁴ is an alkyl group containing 1 to 4 carbon atoms or anhydroxyalkyl group containing 2 or 3 carbon atoms, wherein the weightratio of (a) (b) to is 10:(0.5 to 5):, and wherein the weight ratio ofthe zwitterionic surfactant (c) to the ampholytic surfactant (d) is from1: (0.1 to 0.5).
 2. The composition of claim 1 wherein the anionicsurfactant comprises an alkyl ether sulfate corresponding to formula(III): R⁶O(C₂H₄O)_(m)—SO₃ ⁽⁻⁾M⁽⁺⁾  (III) wherein R⁶ is an alkyl oralkenyl group containing 12 to 18 carbon atoms, m is a number of from 1to 4 and M⁽⁺⁾ is an alkali metal, magnesium, ammonium or alkanolammonium ion.
 3. The composition of claim 2 comprising at least 5percent by weight of the alkyl ether sulfate.
 4. The composition ofclaim 1 wherein the alkyl glycoside or alkyl oligoglycoside correspondsto the formula R⁷(G)_(x), wherein R⁷ is a linear alkyl group containing8 to 16 carbon atoms and (G)_(x) is a glucoside or an oligoglucosideunit with a degree of oligomerization x, of from 1 to
 2. 5. Thecomposition of claim 1 wherein the zwitterionic surfactant (c) comprisesa cocoamidopropyl betaine, wherein R¹ of formula (I) is a R⁵CONH—(CH₂)₃—group, wherein R⁵CO is derived from a C₁₂₋₁₈ cocofatty acid or palmkernel oil fatty acid, and R² and R³ are methyl groups.
 6. Thecomposition of claim 1, wherein the ampholytic surfactant (d) comprisesa cocoamphoglycinate wherein R¹ of formula (II) is a R⁵CONH—(CH₂)₃—group wherein R⁵CO is derived from a C₁₂₋₁₈ cocofatty acid or palmkernel oil fatty acid, and R⁴ is a hydroxy ethyl group.
 7. Thecomposition of claim 1 comprising less than 30 percent by weight ofwater.
 8. The composition of claim 1 comprising less than 5 percent byweight of the anionic surfactant (a).
 9. The composition of claim 1comprising 5 to 20 percent by weight of the anionic surfactant (a).